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Activated carbon (AC) supported MgO (MgO@AC) for CO2 capture has been facilely prepared with Mg(NO3)2 as precursor by a solid-state heat dispersion method. The prepared MgO@AC adsorbents with different magnesium loadings were characterized by X-ray diffraction (XRD), N2 adsorption/desorption and scanning electron microscope (SEM), and were investigated for the CO2 adsorption capacity, CO2 adsorption selectivity and cyclic stability. The characterization results reveal that the precursor of Mg(NO3)2 can be highly dispersed on the surfaces of the AC support and converted to MgO during the activation process at high temperatures. The experimental results show that the MgO@AC adsorbent with the MgO loadings of 5 mmol/g AC support achieves a high CO2 adsorption capacity, high CO2/N2 adsorption selectivity and excellent reversibility. Its good adsorption performance and facile fabrication process make it a promising adsorbent for CO2 capture from flue gases. In addition, the isosteric heat of CO2 adsorption on this adsorbent was calculated from the CO2 adsorption equilibrium isotherms at different temperatures using the Clausius–Clapeyron equation, the values are in the range of 45.4–20.1 kJ/mol.

Zeolite Y supported MgO (denoted as MgO@Y) composites have been successfully prepared using Mg(NO3)2 as precursor via a facile solid-state heat dispersion approach. The samples are characterized by X-ray diffraction and N2 adsorption/desorption, and investigated for CO2 adsorption performance including adsorption capacity, adsorption selectivity and stability. The results reveal that MgO can be highly dispersed on the surfaces of zeolite Y support after the activation at high temperatures, and the monolayer dispersion capacity of MgO on zeolite Y support is 3 mmol/g zeolite Y. The resulting MgO(3.0)@Y adsorbent with the magnesium loadings of 3 mmol/g zeolite Y displays a high CO2 adsorption capacity of 2.78 mmol/g at 500 kPa, which is about 28% higher than that of zeolite Y support. Moreover, the MgO(3.0)@Y adsorbent displays a high CO2/N2 adsorption selectivity of 32 and a excellent cyclic stability. Its good performance as well as its facile preparation process make it attractive candidate for the adsorption of CO2 in flue gas vents. In addition, the isosteric heat of CO2 adsorption on the MgO(3.0)@Y sample was calculated from the Clausius–Clapeyron equation, and the values the isosteric heats of adsorption lie in the range of 27.8–20.0 kJ/mol.

In this work, activated carbon (AC) supported CuCl (CuCl@AC) prepared with CuCl2 as precursor is investigated for CO separation from the synthesis gas mixture. Firstly, the CuCl@AC adsorbents are investigated for their CO reversible adsorption capacity at an operation temperature of 303 K. And a vacuum pressure swing adsorption (VPSA) process of CO separation from syngas utilizing the prepared CuCl@AC adsorbent is investigated at ambient temperature and 0.79 MPa through a dynamic optimization with Aspen Adsorption software. The integrated model is closer to a realistic PSA process, making the results of the simulation and optimization more convincing. The adsorption result reveals that the obtained CuCl@AC adsorbent with the copper loading of 7 mmol g−1 AC achieves a high reversible CO adsorption capacity and adsorption selectivity. The simulation result shows that, under optimal conditions, the CO product with the purity of 98.1 vol% can be separated from the syngas with the CO concentration of 32.3 vol% utilizing the prepared CuCl@AC adsorbent, and the recovery of CO is 92.9%.

A seed-induced method was applied to synthesize a series of ZSM-5 aggregates using silicalite-1 (S-1) as seeds. The samples were characterized by several techniques and studied in the methanol-to-gasoline (MTG) conversion reaction in a continuous fixed-bed reactor. The results showed that the molar ratios of Na2O/SiO2 and H2O/SiO2 in the precursors had great effects on the physicochemical and catalytic properties. The ZSM-5 aggregates with the highest crystallinity, external surface areas, micropore volumes, mesopore volumes and small primary crystal and aggregate sizes, obtained with the molar composition of 0.12Na2O–1SiO2–0.02Al2O3–25H2O-0.01Seed in the precursor, exhibited the highest stability.